The trend towards miniaturization of microelectronic devices such as micro-sensors is necessitating the development of miniaturized power supplies. Batteries and solar cells are traditional power sources for such microelectronic devices. However, the power supplied by batteries dissipates over time requiring replacement of the batteries on a periodic basis. Solar cells, although having an effectively unlimited useful life, may only provide a transient source of power as the sun or other light sources may not always be available.
Thermoelectric generators are energy sources that convert thermal energy into electrical energy over an essentially unlimited lifetime. A thermoelectric generator produces a voltage in response to a thermal gradient across the thermoelectric generator. The thermal gradient may be provided by a heat source on one side of the thermoelectric generator and a lower-temperature heat sink on an opposite side of the thermoelectric generator. Heat from the heat source may flow through the thermoelectric generator prior to entering the heat sink where the heat may be rejected to the environment. The thermoelectric generator may be housed or contained within an interior of a thermoelectric energy harvesting system or module. Increasing the amount of heat flow through the thermoelectric generator and minimizing the shunting of heat flow around the thermoelectric generator may result in an increase in the operating efficiency of the thermoelectric energy harvesting system.
Certain thermoelectric energy harvesting systems may include electronic components to condition the voltage produced by the thermoelectric generator prior to delivery to a load. Electronic components may also be provided to perform application-specific functions. Electronic components typically have a maximum rated temperature up to which the electronic components may operate on a nominal basis. Approaching the maximum rated temperature of the electronic components may result in a reduction in the performance of the electronic components. Exceeding the maximum rated temperature of the electronic components may result in damage or failure of the electronic components. A failure of the electronic components may compromise the electricity-producing capability of the thermoelectric generator.
As can be seen, there exists a need in the art for a system and method of minimizing the heating of electronic components that may be included in a thermoelectric energy harvesting system. In addition, there exists a need in the art for increasing the heat flow through the thermoelectric generator and for minimizing the shunting of heat flow around the thermoelectric generator as a means to improve the operating efficiency of the thermoelectric energy harvesting system.